diff --git a/elastic.js/index.d.ts b/elastic.js/index.d.ts
index 9e25076906..e8b57c5cb7 100644
--- a/elastic.js/index.d.ts
+++ b/elastic.js/index.d.ts
@@ -6765,7 +6765,7 @@ declare module elasticjs {
     /*
      Allows you to set a specified filter on this request object.
      */
-    filter(filter: Object | Filter): Request;
+    filter(filter: Filter): Request;
 
     /*
      A search result set could be very large (think Google). Setting the